Feature request: Annotate Pod template

[Nuru]

When Forecastle's configuration changes, it needs to be restarted to load the changes. I know Stakater's solution is Reloader, but Helm also has a solution, which is to annotate the Pod template with a checksum of the configuration.

Ideally, the Forecastle chart would do this automatically. At a minimum, the chart should allow for annotations of the Pod template much like it allows annotation of the Deployment itself.

[usamaahmadkhan]

@Nuru thanks for opening the issue. PRs are welcome :)